IN-SITU RADIOTRACER STUDIES OF HCOOH ADSORPTION ON N-SI(100) ELECTRODE

The application of radiotracer method in the in situ studies of adsorp tion on semiconductor electrodes has been described. Using this techni que the adsorption of HCOOH on n-Si(100) electrode has been studied an d the surface concentration of the adsorbate determined. The adsorptio n takes place in the potential range of -0.5-1.0V. It has been found t hat adsorption of HCOOH is an irreversible process. The dependence of the surface concentration of adsorbed species on the bulk concentratio n of HCOOH has been determined, too. The epm and eps values at the sur face concentration close to saturation are equal to 0.4 and 0.9, respe ctively. It has been found that adsorbed species are arranged in two l ayers. It is proposed that the first layer is formed by COOH radicals and the second layer is formed by HCOOH molecules. Both layers are mos t likely linked by hydrogen bonds.